1. Field of the Invention
The present invention relates to a vehicular driving force distribution system comprising: a differential device to which torque is supplied from a driving source; and a torque distribution mechanism for distributing the torque supplied to the differential device between left and right wheels in an arbitrary ratio.
2. Description of the Related Art
Such a vehicular driving force distribution system is disclosed in Japanese Patent Application Laid-open No. 7-12426. In this vehicular driving force distribution system, an oil pump is driven by increasing the rotational speed of one of right and left axles, and a hydraulic control circuit for a torque distribution mechanism is operated by a hydraulic pressure produced by the oil pump, thereby distributing torque between right and left wheels.
In this conventional distribution device, since the rotation of one of the right and left axles is increased to drive the oil pump, a differential device sometimes functions depending on the condition of road surface, so that one of the right and left wheels races or run idle. In such a case, there is a possibility that the axle of the other wheel stops rotating and the oil pump becomes incapable of being operated.